Process of purifying and preserving raw sugar.



' UNITED STATES PATENT O FICE.

MORIZ WEINRICH, OF YONKERS, NEW YORK.

PROCESS OF PURIFYING AND PRESERVING RAW SUGAR.

SPECIFICATION forming part of Letters Patent No. 711,603, dated October 21, 1902.

Application filed February 5, 1902.

To all whom it may concern.-

Be it known that I, MORIZ WEINRICH, a citizen of the United States, residing at Yonkers, in the county of Westchester and State of New York, have invented certain new and useful Improvements in Processes of Purifying and of Preserving Raw Sugar; and I do hereby declare the following to be a full,

clear, and exact description of the invention, such as will enable others skilled in the art to 'whichit appertains to make and use the same.

My invention relates to a treatment of raw sugar before it undergoes the ordinary refining process. Itinsures a more energetic purification than heretofore attained and removes also when applied to raw beet-sugar the objectionable smell and taste whichbecome concentrated in its residual syrup or molasses and which has rendered such sy'rup so far hardly fit for human food. Besides, raw sugar which has been treated by my process can be stored for a long time without undergoing any decomposition of its crystallized or crystallizable sugar. To attain this object, I proceed as follows:

The raw sugar to be treated ought to contain from three to four per cent. of moisture. If it should contain less moisture, the difference can be easily added in the shape of expanded steam or of atomized water. To the raw sugar is added and mixed with it intimately and uniformly from -two to four per cent. (according to the quality of the sugar) of finely-powdered burnt lime, (OaO.) This can be done either in some suitable mixing device, or a certain quantity of the raw sugar is spread in a thin layer upon a floor. The powdered lime is then added uniformly on top of the layer by means of a fine sieve and then mixed well with the sugar with scoops. The lime will combine with the Water and the sugar of the molasses, or mother-liquor, which coats the crystals to a sucrate of lime, whereby the temperatureis raised, and the lime will decompose simultaneously a part of the albuminous and other organic foreign matters and also any invert sugar contained in such molasses. As a proof of such decomposition a strong smell of ammonia and of other volatile substances will be perceptible. As soon as the lime has been mixed Serial No. 92,716. (No specimens.)

into the sugar it is thrown into a revoluble drum, which, like a granulator, is provided with lifting-ribs and is heated by steam and through which drum a current of air is maintained. In this drum the intimate mixing is completed and the sugar heated up at the same time, whereby the action of the lime is brought to its full effect, and the repeated airing of every sugar-crystal facilitates the escape of all the volatile matter decomposed by said action of the lime. The sucrate of lime formed by the described treatment will adhere in small particles to the crystals of the treated sugar. This sucrate is not soluble in syrup or in steam, while the impurities surrounding it are. Bya systematic washing of the treated raw sugar with syrups or with steam, or with both, by means of suitable devices as generally used inthe sugar industry it is feasible to divide it, onone hand, into a thoroughly washed sugar, with adhering particles of pure sucrate of lime and, on the other hand, into a wash-syrup of very low purity. Such a perfect separation of pure sugar and of impurities at the beginning of the refining process has not heretofore been attained. The ordinary lime used in the sugar industry can be used also with this process, and it may contain several per cent. of impurities like alumina, silica, magnesia, &c. To give satisfaction, it ought to be'freshly burned and has to be ground into an impalpable powder.

been washed, is dissolved. In both cases the washed sugar and the wash-syrup, as well as the whole dissolved sugar, will be strongly alkaline. This strong alkalinity has to be reduced to a slight alkalinity, either by means of diluted phosphoric acid or of carbonic-acid 1 from beet-sugar treated in this way will be of a pleasant flavor and taste and free from the offensive beet-smell.

It is a well-known fact that raw sugar, especially raw cane-sugar, which is generally acid, will lose by long storing a certain percentage of its contents of crystallizable sugar, because some of this crystallizable sugar is converted through increasing acidity, accelerated by hot and damp weather, into invert sugar. Great losses are continuously sustained in this Way by holders of raw canesugar. By the use of the above-described process such deterioration and consequent losses can be Wholly prevented. The added lime will destroy any invert sugar which may be contained in the syrup coating the sugarcrystals, and the strong alkalinity of such syrup will prevent any conversion of crystallizable sugar into invert sugar.

I claim 1. The described process of purifying and of preserving raw sugar, consisting in mixing intimately and uniformly with the raw sugar a small percentage of finely-powdered burnt lime, thus forming a sucrate of lime with the sugar of the molasses covering the sugar-crystals, and decomposing simultaneously organic impurities contained in said molasses and then heating and airing the mixture, substantially as set forth.

2. The described process of purifying and of preserving raw sugar, consisting in mixing intimately and uniformly with the raw sugar a small percentage of finely-powdered burnt lime, thus forming a sucrate of lime With the sugar of the molasses covering the sugarcrystals, and decomposing simultaneously organic impurities contained in said molasses, then heating and airing the mixture, then by washing separating the impurities from the sugar-crystals and the sucrate of lime, and finally neutralizing the added lime from the dissolved sugar-crystals and sucrate of lime and from the wash-syrup, substantially as set forth.

3. The described process of purifying and of preserving raw sugar, consisting in mixing intimately and uniformly with the raw sugar a small percentage of finely-powdered burnt lime, thus forming a sucrate of lime with the sugar of the molasses covering the sugar-crystals, and decomposing simultaneously organic impurities contained in said' molasses, then heating and airing the mixture, then dissolving said mixture and finally neutralizing from it the added lime, substantially as set forth.

In testimony whereof I have affixed my signature in presence of two witnesses.

MORIZ WEINRICH. Witnesses:

JAMES S. FITCH, ADOLF KLEIN. 

